This paper uses the bootstrap rolling-window Granger causality method to investigate the relationship between U.S. monetary policy (UMP) and crude oil price (COP). The method addresses the limitations of ignoring the instability of coefficients in the previous literature and supports the partial equilibrium model from the perspective of the time domain, which enriches the existing literature. The finding reveals a positive effect from COP to UMP, implying that the unexpected rise in COP may push UMP from expansionary into restrictive since the rising COP increases the U.S. inflation pressure. Meanwhile, the economic evidence shows that UMP has a negative effect on COP, which implies that expansionary monetary policy increases the rising pressure on COP. This finding is consistent with the partial equilibrium model, which states that UMP specifically influences COP, including consumption channels and financial channels. Specifically, the expansionary monetary policy may reduce companies' investment costs and stimulate investment and consumption, increasing the demand for crude oil and pushing COP. Given the critical role played by the monetary policy and COP in the U.S., the detailed understanding derived from the relationship between the variables may help the investors and policymakers forecast the energy price trend and adjust the policy strategies promptly.

中文翻译：

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美国货币政策：原油价格的推手？

本文采用自举滚动窗格兰杰因果关系方法研究美国货币政策（UMP）与原油价格（COP）之间的关系。该方法解决了以往文献中忽略系数不稳定性的局限性，从时域角度支持部分均衡模型，丰富了现有文献。这一发现揭示了 COP 对 UMP 的积极影响，这意味着 COP 的意外上升可能会推动 UMP 从扩张性转为限制性，因为 COP 的上升会增加美国的通胀压力。同时，经济证据表明UMP对COP有负面影响，这意味着扩张性货币政策增加了COP的压力。这一发现与部分均衡模型一致，该模型指出UMP具体影响COP，包括消费渠道和金融渠道。具体而言，扩张性货币政策可能降低企业投资成本，刺激投资和消费，增加原油需求，推动COP。鉴于货币政策和COP在美国发挥着至关重要的作用，对变量之间关系的详细了解可以帮助投资者和政策制定者预测能源价格走势并及时调整政策策略。